Hot-air furnace



S. H. DENT.

HOT AIR FURNACE.

APPLICATION FILED JAN.14, 1920.

1,361,371, Patented Dec. 7, 1920.

3 SHEETSSHEET l- TEE- imme/whom S. H. DENT.

HOT AIR FURNACE.

APPLICATION FILED JAN.14,1 920.

Patented Dec. 7, 1920.

3 SHEETSSHEET 2.

3mm SJZDeni.

S. H. DENT.

HOT AIR FURNACE- APPLI CATION ,FILED JAN. 14, 1920.

1,3 1,37 Patented Dec. 7, 1920.

3 SHEETS-SHEET 3.

' awe/whoa SJtlDeni PATENT OFFICE.

SAMUEL H. DENT, OF CHICAGO, ILLINOIS.

HOT-AIR FURNACE. a

Specification of Letters Patent.

Patented Dec. 7, 1920.

Application filed January 14, 1920. Serial No. 351,472.

To all whom it may concern:

Be it known that I, SAMUEL H. DENT, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Hot-Air Furnaces, of which the following is a specification.

This invention relates to hot air furnaces and its object is to provide a structure in which an air heating chamber is'so arrangedthat the air is rapidly heated, the escaping smoke and furnace gases being also utilized to heat the air. I

The invention also has for its object to provide a novel and improved means for evenly distributing the air to the outlets of the air heating chamber, and to provide said chamber with an inclosure whereby it is isolated from the external atmosphere and is thus prevented from being chilled, with the result that a considerable saving of fuel is effected.

Other objects and advantages of the invention will be pointed out in the detailed description appearing hereinafter, and in order that the same may be better understood, reference is had to the accompanying ,drawlngs forming a part ofthis specification.

The preferred embodiment ofthe invention has been shown, but it will be understood that various changes andmodifications may be made without a departure from the spirit and scope of the invention as claimed hereinafter.

In the drawings,

Figure 1 is an elevation of the furnace;

Fig. 2 is a central: vertical section thereof;

Figs. 8, 4, 5, and 6 are horizontal sections on the lines 3+3, 4- 1, 55 and 6-4), respectively of Fig. 2 and Fig. 7 is a vertical section on the line 77 of Fig. 5.

Referring specifically to the drawings, 10, 11, 12 and 13 denote respectively, the brick front, side and rear walls of the furnace, These walls form a rectangular inclosure for the combustion chamber and other interior parts of the furnace. The top of the inclosure is covered by a metal plate l lwhich is sunken toward the center to hold the usual filler or bed 15 of sand. A marginal cornice 16 completes the top of the brick structure.

Back of the front wall 10 is an inclosure of brick sidewalls 17 and a rear wall 18 inside of which is mounted a grate frame 19, and a grate 20, with an ash pit 21 beneath the same. The space above the grate 20 is the combustion chamber of the furnace, the same being formed by the walls 10, 17 and 18. The wall 10 has a fuel chargmg door 22, a draft door 23, and an ash door 24, nothing being claimed. for this arrangement of parts.

The walls 17 and 18 are flared at the top as shown in Fig. 2 and are arranged to give the combustion chamber acircular shape, and to support a circular cast iron plate 25 which forms a top closure for the combustion chamher. As the plate 25 does not reach over to the front wall 10, the space is filled by a brick arch 26, as shown in Fig. 7. w

The walls 17 and 18 are doubled as shown at 17 and 18 to inclose a sheet metal wall 27 therebetween. This wall 27 is flared at the top, as shown at 27 and here assumes a conical contour, and terminates in an annular upstanding rim 27". The walls 10, 11, 12 and 13, and the walls forming the combustion chamber of the furnace, are spaced to produce the air jacket or chamber of the furnace, and the object of the walls 27 is to completely separate the combustion chamber from the air jacket, so that if the wall of the former crumbles in places'from the extreme heat, smoke and fuel gases will not escape 1nto the air jacket. Asthe metal acket or wall 27 remain intact, and is not liableto damage from the heat, repairs in the combustion chambercan be easily made.

Between the middle of the top plate 14 and the cast iron plate 25, is a perforated, vertically positioned flue 28 closed at its ends by said plates; The plate 25 also has an upstanding marginal wall 29 forming a drum which surrounds the lower portion of the flue 28. The top of this drum is closed by a late 30 which also extends over to the rim 2 b of the walls 27 to cover the annular side Walls 11 and 12 and the walls 17 a forming the air jacket or chamber, as shown dotted in Fig. 7, whereas the partitions 34 rise to a height a short distance above the perforated plate 30, being inclined forwardly as shown dotted in Fig. 7 to help make up the absence of the partitions 33 at the upper portion of the furnace.

short partition 36 is provided at the front rising from the arch 26 to the height of the partitions 34 and 35. The four partitions support, with. angle iron inserts 37, a short square wall 38 of brick-work extending around the upper portion of the flue 28 which projects above the plate 30, said wall forming a hot air distributing chamber closed at the top by the plate 14 and at the bottom by the plate 30. This chamber contains four gates 40 of heavy sheet metal set in the form of a cross, as shown in Fig. 5, and forming partitions in the chamber when they are in erect position. These gates are pivotally supported at the bottom to swing about horizontal axes, by hinge rods 41 slidable in the bottom of the gates, each rod having an external actuating handle 42 carrying a locking pin 43, which latter, when the gates are up in erect position, seat in keeper apertures in the outer walls of the furnace as shown in Fig. 7 Drawin the handles 42 out retracts the .pins 43, permitting the gates 40 to swing down onthe plate 30 as shown dotted in Fig. 5. Each gate 40 may be independently operated by the means here described. Between each two adjacent gates, the hot air distributing chamber they occupy has an air flue or service outlet 44.

The smoke from the combustion chamber rises through an outlet 45 into the annular chamber defined by the walls 29 and 27*, being deflected laterally as shown by the arrows in Fig. .6, by a barrier block 46, so

' that it takes a circular path to the remote side of the barrier where it passes down into the outlet flue 47 shown in Fig. 2.

The air jacket or chamber of the furnace has inlet doors 48 (see Fig. 2), and side draft tubes 49. (see Fig. 3) are provided to supply fuel and air to the front and rear ends of the combustion chamber. The fuel at the rear end of the combustion chamber therefore does not remain inactive as is freuently the case with front draft furnaces. einforcing bolts 50 (see Fig. 4), are provided to hold the inner and outer structures firmly against distortion or displacement.

As the cast iron plate 25 receives considerable heat, the hot air receiving drum formed by the wall 29 is located directly above it, and from the drum, the air passes through the perforations 32 and 31 into the distributing chamber partitioned off by the gates 40. The purpose of the gates 40 is to distribute the heat evenly to the outlets 44, and to break up any circulation of hot air tending to deliver more hot air into the outlets 44 at the chimney side of the furnace than elsewhere, as occasioned by the draft. The gates may be swung down, one of such being so shown dotted in Fig. 5. The passage of hot smoke and furnace gases around the wall 29 as hereinbefore described also heats the air in the drum formed by the said wall. It will also be noted thatthe drum is completely surrounded by brickwork, and hence it is isolated from the eX- ternal atmosphere and prevented from getting chilled. The brick-work holds the heat,

and the furnace is therefore economical in fuel consumption, and remains hot many hours after the fire dies down at nlght.

The air in the jacket of the furnace can pass into the chamber containing the gates 40 as the wall 38 does not extend down to the plate 30 and the wall 27*, there being thus left an opening for entry of air into said chamber. The wall 38 is supported by the angle irons 37, the latter seating on top of the partitions 34, 35 and 36. In Fig. 2 the partitions 34 are shown in sections at the top as they are here at the middle of the furnace, and from which they slant rearwardly as shown dotted in Fig. 7. The par- .titions 34, 35 and 36 as well as the'partitions 33 serve to spare the inner and outer walls of the furnace, and to prevent bulging out or caving in from the heat.

I claim:

1. In a hot air furnace, a combustion chamber, a hot air drum seating on top of said chamberand forming a closure therefor, a hot air distributing'chamber having a perforated bottom forming the top of the drum, and partitions in said chamber dividing the same into a plurality of sections,

each sectionhaving a hot air outlet, said partitions being adjustable to establish communication between the sections.

2. In a hot air furnace, a combustion chamber, a hot air drumseating on top of said chamber and forming a closure therefor, a hot air distributing chamber having a perforated bottom forming the top of the drum, a perforated flue in the drum and extending into the distributing chamber, and partitions in said chamber dividing the same into a plurality of sections, each section having a hot air outlet, said partitions being adj ustable to establish communication between the sections.

3. In a hot air furnace, a combustion chamber, a hot air drum seating on top of said chamber and forming a closure therefor, a hot air distributing chamber above the drum and supplied by the latter, partitions in said chamber dividing the same into a plurality of sections, each section'having a hot air outlet, said partitions being adjustable to establish communication between the sections, and a smoke flue around the drum into which the combustion chamber discharges. 1

4:. In a hot air furnace, a combustion chamber, a hot air drum seating on top of said chamber and forming a closure therefor, a hot air distributing chamber above the drum and supplied by the latter, partitions in said chamber dividing the same into a plurality of sections, each section having a hot air outlet, said partitions being adjustable to establish communication between the sections, a smoke flue around the drum into which the combustion chamber disthe outlet of the smoke place.

5. In a hot air furnace, a combustion,

chamber, a hot air drum seating on top of said chamber and forming a closure therefor, a hot air distributing chamber above the drum and supplied by the latter, and partitions in said chamber dividing the same into a plurality of sections, each section having a hot air outlet, said partitions'being adjustable to establish communication between the sections, and a hot air jacket around the distributing chamber.

In testimony whereof I aflix my signature.

SAMUEL H. DENT. 

